{
  "cveId": "CVE-2026-46031",
  "url": "https://patchblox.com/security/cve/CVE-2026-46031",
  "summary": "CVE-2026-46031 is fixed in linux on 1 platform, first by DEBIAN-CVE-2026-46031, released May 27, 2026. It is not reported as exploited. Patch Radar priority: High.",
  "title": "net: ks8851: Reinstate disabling of BHs around IRQ handler",
  "description": "In the Linux kernel, the following vulnerability has been resolved:  net: ks8851: Reinstate disabling of BHs around IRQ handler  If the driver executes ks8851_irq() AND a TX packet has been sent, then the driver enables TX queue via netif_wake_queue() which schedules TX softirq to queue packets for this device.  If CONFIG_PREEMPT_RT=y is set AND a packet has also been received by the MAC, then ks8851_rx_pkts() calls netdev_alloc_skb_ip_align() to allocate SKBs for the received packets. If netdev_alloc_skb_ip_align() is called with BH enabled, then local_bh_enable() at the end of netdev_alloc_skb_ip_align() will trigger the pending softirq processing, which may ultimately call the .xmit callback ks8851_start_xmit_par(). The ks8851_start_xmit_par() will try to lock struct ks8851_net_par .lock spinlock, which is already locked by ks8851_irq() from which ks8851_start_xmit_par() was called. This leads to a deadlock, which is reported by the kernel, including a trace listed below.  If CONFIG_PREEMPT_RT is not set, then since commit 0913ec336a6c0 (\u0022net: ks8851: Fix deadlock with the SPI chip variant\u0022) the deadlock can also be triggered without received packet in the RX FIFO. The pending softirqs will be processed on return from spin_unlock_bh(\u0026ks-\u003Estatelock) in ks8851_irq(), which triggers the deadlock as well.  Fix the problem by disabling BH around critical sections, including the IRQ handler, thus preventing the net_tx_action() softirq from triggering during these critical sections. The net_tx_action() softirq is triggered once BH are re-enabled and at the end of the IRQ handler, once all the other IRQ handler actions have been completed.   __schedule from schedule_rtlock\u002B0x1c/0x34  schedule_rtlock from rtlock_slowlock_locked\u002B0x548/0x904  rtlock_slowlock_locked from rt_spin_lock\u002B0x60/0x9c  rt_spin_lock from ks8851_start_xmit_par\u002B0x74/0x1a8  ks8851_start_xmit_par from netdev_start_xmit\u002B0x20/0x44  netdev_start_xmit from dev_hard_start_xmit\u002B0xd0/0x188  dev_hard_start_xmit from sch_direct_xmit\u002B0xb8/0x25c  sch_direct_xmit from __qdisc_run\u002B0x1f8/0x4ec  __qdisc_run from qdisc_run\u002B0x1c/0x28  qdisc_run from net_tx_action\u002B0x1f0/0x268  net_tx_action from handle_softirqs\u002B0x1a4/0x270  handle_softirqs from __local_bh_enable_ip\u002B0xcc/0xe0  __local_bh_enable_ip from __alloc_skb\u002B0xd8/0x128  __alloc_skb from __netdev_alloc_skb\u002B0x3c/0x19c  __netdev_alloc_skb from ks8851_irq\u002B0x388/0x4d4  ks8851_irq from irq_thread_fn\u002B0x24/0x64  irq_thread_fn from irq_thread\u002B0x178/0x28c  irq_thread from kthread\u002B0x12c/0x138  kthread from ret_from_fork\u002B0x14/0x28",
  "published": "2026-05-27T14:17:22Z",
  "severity": "Moderate",
  "cvss": 7.5,
  "cvssVector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
  "epss": 0.0037,
  "epssPercentile": 0.31077,
  "priority": "High",
  "priorityTier": 3,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "vendorAdvisory": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-46031",
  "fixes": [
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 12.15 (bookworm)",
      "fixedVersion": "6.1.176-1",
      "fix": "DEBIAN-CVE-2026-46031",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-46031",
      "released": "2026-05-27T17:38:13Z"
    },
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 13.5 (trixie)",
      "fixedVersion": "6.12.86-1",
      "fix": "DEBIAN-CVE-2026-46031",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-46031",
      "released": "2026-05-27T17:38:13Z"
    },
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 14",
      "fixedVersion": "7.0.4-1",
      "fix": "DEBIAN-CVE-2026-46031",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-46031",
      "released": "2026-05-27T17:38:13Z"
    }
  ],
  "noFixYet": [],
  "dataAsOf": "2026-11-08T13:06:02Z",
  "attribution": {
    "text": "Data: Patchblox Patch Radar",
    "url": "https://patchblox.com/security/patch-radar",
    "terms": "https://patchblox.com/security/patch-radar/use-the-data"
  }
}